In my wiki I used #forminput several times for a longer period to pass values to new pages.
EXAMPLE:
{{#forminput:form=Dokument |size= 110 |default value=Datei:Testdatei.pdf |autocomplete on category= Dokument |Dokument[Dokumenttyp]=Angeb |Dokument[gehört zu Beschaffungsvorgang]={{FULLPAGENAMEE}} |Dokument[Geschäftspartner]={{urlencode:AnyCompany Ltd}} |AKS[UstNr]=01 }}
I cannot say from wich point of time #forminput runs into the following error
Error Message: An internal server error occurred. Please try again later.
This flaw has come with some Version after 5.x.
I found that this happens in any case when values are passed to a "multiple" form. In the example "AKS" is a multiple form within Form:Dokument. If I remove the line |AKS[..... from the #forminput tag all is fine.
When adding a "counter" to the string things change from case to case:
If the counter is 0
|AKS[0][UstNr]=01
the error does not occur but no data is transferred to the "multiple" form.
On any other counter the error occurs. like
|AKS[1][UstNr]=01 |AKS[2][UstNr]=01
This was already discussed on the mailing list semediawiki-user@lists.sourceforge.net